For the first time in U.S. history, more than one of every 100 adults is in jail or prison, according to a new report documenting America's rank as the world's No. 1 incarcerator. It urges states to curtail corrections spending by placing fewer low-risk offenders behind bars.

Using state-by-state data, the report says 2,319,258 Americans were in jail or prison at the start of 2008 - one of every 99.1 adults. Whether per capita or in raw numbers, it's more than any other nation.

The report, released Thursday by the Pew Center on the States, said the 50 states spent more than $49 billion on corrections last year, up from less than $11 billion 20 years earlier. The rate of increase for prison costs was six times greater than for higher education spending, the report said.